app_settings.h

// Read an INI file into easy-to-access name/value pairs.

// inih and INIReader are released under the New BSD license (see LICENSE.txt).
// Go to the project home page for more info:
//
// https://github.com/benhoyt/inih
/* inih -- simple .INI file parser

inih is released under the New BSD license (see LICENSE.txt). Go to the project
home page for more info:

https://github.com/benhoyt/inih

*/

#ifndef __INI_H__
#define __INI_H__

/* Make this header file easier to include in C++ code */
#ifdef __cplusplus
extern "C" {
#endif

#include <stdio.h>

	/* Typedef for prototype of handler function. */
	typedef int(*ini_handler)(void* user, const char* section,
		const char* name, const char* value);

	/* Typedef for prototype of fgets-style reader function. */
	typedef char* (*ini_reader)(char* str, int num, void* stream);

	/* Parse given INI-style file. May have [section]s, name=value pairs
	(whitespace stripped), and comments starting with ';' (semicolon). Section
	is "" if name=value pair parsed before any section heading. name:value
	pairs are also supported as a concession to Python's configparser.

	For each name=value pair parsed, call handler function with given user
	pointer as well as section, name, and value (data only valid for duration
	of handler call). Handler should return nonzero on success, zero on error.

	Returns 0 on success, line number of first error on parse error (doesn't
	stop on first error), -1 on file open error, or -2 on memory allocation
	error (only when INI_USE_STACK is zero).
	*/
	int ini_parse(const char* filename, ini_handler handler, void* user);

	/* Same as ini_parse(), but takes a FILE* instead of filename. This doesn't
	close the file when it's finished -- the caller must do that. */
	int ini_parse_file(FILE* file, ini_handler handler, void* user);

	/* Same as ini_parse(), but takes an ini_reader function pointer instead of
	filename. Used for implementing custom or string-based I/O. */
	int ini_parse_stream(ini_reader reader, void* stream, ini_handler handler,
		void* user);

	/* Nonzero to allow multi-line value parsing, in the style of Python's
	configparser. If allowed, ini_parse() will call the handler with the same
	name for each subsequent line parsed. */
#ifndef INI_ALLOW_MULTILINE
#define INI_ALLOW_MULTILINE 1
#endif

	/* Nonzero to allow a UTF-8 BOM sequence (0xEF 0xBB 0xBF) at the start of
	the file. See http://code.google.com/p/inih/issues/detail?id=21 */
#ifndef INI_ALLOW_BOM
#define INI_ALLOW_BOM 1
#endif

	/* Nonzero to allow inline comments (with valid inline comment characters
	specified by INI_INLINE_COMMENT_PREFIXES). Set to 0 to turn off and match
	Python 3.2+ configparser behaviour. */
#ifndef INI_ALLOW_INLINE_COMMENTS
#define INI_ALLOW_INLINE_COMMENTS 1
#endif
#ifndef INI_INLINE_COMMENT_PREFIXES
#define INI_INLINE_COMMENT_PREFIXES ";"
#endif

	/* Nonzero to use stack, zero to use heap (malloc/free). */
#ifndef INI_USE_STACK
#define INI_USE_STACK 1
#endif

	/* Stop parsing on first error (default is to keep parsing). */
#ifndef INI_STOP_ON_FIRST_ERROR
#define INI_STOP_ON_FIRST_ERROR 0
#endif

	/* Maximum line length for any line in INI file. */
#ifndef INI_MAX_LINE
#define INI_MAX_LINE 200
#endif

#ifdef __cplusplus
}
#endif

/* inih -- simple .INI file parser

inih is released under the New BSD license (see LICENSE.txt). Go to the project
home page for more info:

https://github.com/benhoyt/inih

*/

#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS)
#define _CRT_SECURE_NO_WARNINGS
#endif

#include <stdio.h>
#include <ctype.h>
#include <string.h>

#if !INI_USE_STACK
#include <stdlib.h>
#endif

#define MAX_SECTION 50
#define MAX_NAME 50

/* Strip whitespace chars off end of given string, in place. Return s. */
inline static char* rstrip(char* s)
{
	char* p = s + strlen(s);
	while (p > s && isspace((unsigned char)(*--p)))
		*p = '\0';
	return s;
}

/* Return pointer to first non-whitespace char in given string. */
inline static char* lskip(const char* s)
{
	while (*s && isspace((unsigned char)(*s)))
		s++;
	return (char*)s;
}

/* Return pointer to first char (of chars) or inline comment in given string,
or pointer to null at end of string if neither found. Inline comment must
be prefixed by a whitespace character to register as a comment. */
inline static char* find_chars_or_comment(const char* s, const char* chars)
{
#if INI_ALLOW_INLINE_COMMENTS
	int was_space = 0;
	while (*s && (!chars || !strchr(chars, *s)) &&
		!(was_space && strchr(INI_INLINE_COMMENT_PREFIXES, *s))) {
		was_space = isspace((unsigned char)(*s));
		s++;
	}
#else
	while (*s && (!chars || !strchr(chars, *s))) {
		s++;
	}
#endif
	return (char*)s;
}

/* Version of strncpy that ensures dest (size bytes) is null-terminated. */
inline static char* strncpy0(char* dest, const char* src, size_t size)
{
	strncpy(dest, src, size);
	dest[size - 1] = '\0';
	return dest;
}

/* See documentation in header file. */
inline int ini_parse_stream(ini_reader reader, void* stream, ini_handler handler,
	void* user)
{
	/* Uses a fair bit of stack (use heap instead if you need to) */
#if INI_USE_STACK
	char line[INI_MAX_LINE];
#else
	char* line;
#endif
	char section[MAX_SECTION] = "";
	char prev_name[MAX_NAME] = "";

	char* start;
	char* end;
	char* name;
	char* value;
	int lineno = 0;
	int error = 0;

#if !INI_USE_STACK
	line = (char*)malloc(INI_MAX_LINE);
	if (!line) {
		return -2;
	}
#endif

	/* Scan through stream line by line */
	while (reader(line, INI_MAX_LINE, stream) != NULL) {
		lineno++;

		start = line;
#if INI_ALLOW_BOM
		if (lineno == 1 && (unsigned char)start[0] == 0xEF &&
			(unsigned char)start[1] == 0xBB &&
			(unsigned char)start[2] == 0xBF) {
			start += 3;
		}
#endif
		start = lskip(rstrip(start));

		if (*start == ';' || *start == '#') {
			/* Per Python configparser, allow both ; and # comments at the
			start of a line */
		}
#if INI_ALLOW_MULTILINE
		else if (*prev_name && *start && start > line) {

#if INI_ALLOW_INLINE_COMMENTS
			end = find_chars_or_comment(start, NULL);
			if (*end)
				*end = '\0';
			rstrip(start);
#endif

			/* Non-blank line with leading whitespace, treat as continuation
			of previous name's value (as per Python configparser). */
			if (!handler(user, section, prev_name, start) && !error)
				error = lineno;
		}
#endif
		else if (*start == '[') {
			/* A "[section]" line */
			end = find_chars_or_comment(start + 1, "]");
			if (*end == ']') {
				*end = '\0';
				strncpy0(section, start + 1, sizeof(section));
				*prev_name = '\0';
			}
			else if (!error) {
				/* No ']' found on section line */
				error = lineno;
			}
		}
		else if (*start) {
			/* Not a comment, must be a name[=:]value pair */
			end = find_chars_or_comment(start, "=:");
			if (*end == '=' || *end == ':') {
				*end = '\0';
				name = rstrip(start);
				value = lskip(end + 1);
#if INI_ALLOW_INLINE_COMMENTS
				end = find_chars_or_comment(value, NULL);
				if (*end)
					*end = '\0';
#endif
				rstrip(value);

				/* Valid name[=:]value pair found, call handler */
				strncpy0(prev_name, name, sizeof(prev_name));
				if (!handler(user, section, name, value) && !error)
					error = lineno;
			}
			else if (!error) {
				/* No '=' or ':' found on name[=:]value line */
				error = lineno;
			}
		}

#if INI_STOP_ON_FIRST_ERROR
		if (error)
			break;
#endif
	}

#if !INI_USE_STACK
	free(line);
#endif

	return error;
}

/* See documentation in header file. */
inline int ini_parse_file(FILE* file, ini_handler handler, void* user)
{
	return ini_parse_stream((ini_reader)fgets, file, handler, user);
}

/* See documentation in header file. */
inline int ini_parse(const char* filename, ini_handler handler, void* user)
{
	FILE* file;
	int error;

	file = fopen(filename, "r");
	if (!file)
		return -1;
	error = ini_parse_file(file, handler, user);
	fclose(file);
	return error;
}

#endif /* __INI_H__ */


#ifndef __INIREADER_H__
#define __INIREADER_H__

#include <map>
#include <set>
#include <string>

// Read an INI file into easy-to-access name/value pairs. (Note that I've gone
// for simplicity here rather than speed, but it should be pretty decent.)
class INIReader
{
public:
	// Empty Constructor
	INIReader() {};

	// Construct INIReader and parse given filename. See ini.h for more info
	// about the parsing.
	INIReader(std::string filename);

	// Return the result of ini_parse(), i.e., 0 on success, line number of
	// first error on parse error, or -1 on file open error.
	int ParseError() const;

	// Return the list of sections found in ini file
	const std::set<std::string>& Sections() const;

	// Get a string value from INI file, returning default_value if not found.
	std::string Get(std::string section, std::string name,
		std::string default_value) const;

	// Get an integer (long) value from INI file, returning default_value if
	// not found or not a valid integer (decimal "1234", "-1234", or hex "0x4d2").
	long GetInteger(std::string section, std::string name, long default_value) const;

	// Get a real (floating point double) value from INI file, returning
	// default_value if not found or not a valid floating point value
	// according to strtod().
	double GetReal(std::string section, std::string name, double default_value) const;

	// Get a boolean value from INI file, returning default_value if not found or if
	// not a valid true/false value. Valid true values are "true", "yes", "on", "1",
	// and valid false values are "false", "no", "off", "0" (not case sensitive).
	bool GetBoolean(std::string section, std::string name, bool default_value) const;

private:
	int _error;
	std::map<std::string, std::string> _values;
	std::set<std::string> _sections;
	static std::string MakeKey(std::string section, std::string name);
	static int ValueHandler(void* user, const char* section, const char* name,
		const char* value);
};

#endif  // __INIREADER_H__


#ifndef __INIREADER__
#define __INIREADER__

#include <algorithm>
#include <cctype>
#include <cstdlib>

using std::string;

inline INIReader::INIReader(string filename)
{
	_error = ini_parse(filename.c_str(), ValueHandler, this);
}

inline int INIReader::ParseError() const
{
	return _error;
}

inline const std::set<string>& INIReader::Sections() const
{
	return _sections;
}

inline string INIReader::Get(string section, string name, string default_value) const
{
	string key = MakeKey(section, name);
	return _values.count(key) ? _values.at(key) : default_value;
}

inline long INIReader::GetInteger(string section, string name, long default_value) const
{
	string valstr = Get(section, name, "");
	const char* value = valstr.c_str();
	char* end;
	// This parses "1234" (decimal) and also "0x4D2" (hex)
	long n = strtol(value, &end, 0);
	return end > value ? n : default_value;
}

inline double INIReader::GetReal(string section, string name, double default_value) const
{
	string valstr = Get(section, name, "");
	const char* value = valstr.c_str();
	char* end;
	double n = strtod(value, &end);
	return end > value ? n : default_value;
}

inline bool INIReader::GetBoolean(string section, string name, bool default_value) const
{
	string valstr = Get(section, name, "");
	// Convert to lower case to make string comparisons case-insensitive
	std::transform(valstr.begin(), valstr.end(), valstr.begin(), ::tolower);
	if (valstr == "true" || valstr == "yes" || valstr == "on" || valstr == "1")
		return true;
	else if (valstr == "false" || valstr == "no" || valstr == "off" || valstr == "0")
		return false;
	else
		return default_value;
}

inline string INIReader::MakeKey(string section, string name)
{
	string key = section + "=" + name;
	// Convert to lower case to make section/name lookups case-insensitive
	std::transform(key.begin(), key.end(), key.begin(), ::tolower);
	return key;
}

inline int INIReader::ValueHandler(void* user, const char* section, const char* name,
	const char* value)
{
	INIReader* reader = (INIReader*)user;
	string key = MakeKey(section, name);
	if (reader->_values[key].size() > 0)
		reader->_values[key] += "\n";
	reader->_values[key] += value;
	reader->_sections.insert(section);
	return 1;
}

#endif  // __INIREADER__